The fabrication of integrated circuits (IC) in the semiconductor industry typically employs plasma to create and assist surface chemistry within a plasma reactor necessary to remove material from and deposit material to a substrate. In general, plasma is formed within the plasma reactor under vacuum conditions by heating electrons to energies sufficient to sustain ionizing collisions with a supplied process gas. Moreover, the heated electrons can have energy sufficient to sustain dissociative collisions, and therefore, a specific set of gases under predetermined conditions (e.g., chamber pressure, gas flow rate, etc.) are chosen to produce a population of charged species and chemically reactive species suitable to the particular process being performed within the chamber (e.g., etching processes where materials are removed from the substrate or deposition processes where materials are added to the substrate).
Typically, during plasma processing such as for example during etch applications, it is necessary to “season” the plasma processing system following a period of process system maintenance, i.e. chamber cleaning, process kit replacement, etc. Prior to initiating production, several substrates are processed through the plasma processing system in order to form a “seasoning” film on the chamber interior and, thus, facilitate repeatable process performance for the substrates to follow. The substrates used for “seasoning” are generally coated with a seasoning material, such as photo-resist, to provide a proper seasoning film on the chamber interior. However, during a seasoning process, a non-seasoning substrate, such as a bare silicon substrate, can be mistakenly inserted into the seasoning process. When this occurs, significant particle production and contamination in the seasoned chamber can lead to poor quality production substrates and chamber downtime.